University of Missouri Center for Agroforestry. Noncommercial use only, video used with permission. In alley cropping, an agricultural crop is grown simultaneously with a long-term tree crop to provide annual income while the tree crop matures. Fine hardwoods like walnut, oak, ash and pecan are favored species in alley cropping systems and can potentially provide high value lumber or veneer logs. Learn how nut crops can be another intermediate product and see examples of successful alley cropping practices.